arduous

Reading level: hard

Estimated CEFR level: C1 — Advanced

Estimated from word frequency; not an official CEFR classification.

Definition

adjective characterized by effort to the point of exhaustion; especially physical effort
adjective taxing to the utmost; testing powers of endurance; ; ; - F.D.Roosevelt
adjective difficult to accomplish; demanding considerable mental effort and skill

From Latin arduus (“lofty, high, steep, hard to reach, difficult, laborious”), akin to Irish ard (“high”).

It was an arduous task. — Wanderfoot (The Dream Ship), Cynthia Stockley
Nothing is too arduous for genius. — Paul Clifford — Complete, Edward Bulwer Lytton, Baron Lytton
His interment was an arduous labour. — English Eccentrics and Eccentricities, John Timbs

backbreaking, grueling, gruelling, hard, heavy, laborious, operose, punishing, toilsome

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